“He was hysterical,” said Crown Bhavna Bhangu, reading from an agreed statement of facts on the first day of Lawlor’s trial.

Lawlor, 22, has pleaded not guilty to charges, including impaired driving causing the death of Ellen Silk, of Orillia.

Silk died after Lawlor’s pickup truck veered off the road and crashed into a tree on a Warminster Sideroad, near Orillia, at around 3 a.m. Nov. 20, 2015.

“How do you know you killed someone?” asked Lawlor’s anguished mother on the phone.

“I killed Ellen,” was his desperate answer, and he pleaded with his mother to come, court heard.

“The cause of her death was decapitation,” said Bhangu. She described how the young woman’s body ended up lodged in the back seat behind the driver — her long blond hair and scalp fragments found on a tree.

It was a dark but clear night when Lawlor drove his black Silverado pickup along a stretch of the two-lane paved road, with Silk and two other friends in the vehicle. As he negotiated a sharp bend, he careened into a ditch and travelled 28 metres before crashing into a large tree. He managed to get the vehicle back on the road before realizing the devastating results, court heard.

Court photographs showed the damaged vehicle, with shattered windows, streaks of blood, headlights dangling and a bloodied tree limb stuck in the back of the cab. A case of Budweiser sat in one of the back seats, an open can of beer was found underneath the driver’s seat.